Taiheiyou ni Kakeru Niji
Schoolgirl Mitsuko tries to protect half-Chinese transfer student Yu-Lian from bullies. That night, she discovers Emily, an old American doll. Given to a Japanese child during an exchange in 1921, it was hidden from the "doll burnings" of the anti-Western war period and saved by a brave young girl (Mitsuko's grandmother). At the next day's show-and-tell, Mitsuko tells the story of Emily and encourages Yu-Lian.
(Source: The Anime Encyclopedia)